Cluster shared volumes (CSV) introduced in Windows 2008 R2 is a feature that simplifies the configuration and management of Hyper-V virtual machines (VM) in failover clusters. With CSV, on a failover cluster that runs Hyper-V, multiple virtual machines can use the same disk yet fail over (or move from node to node) independently of one another. CSV provides increased flexibility for volumes in clustered storage—for example, it allows you to keep system files separate from data to optimize disk performance, even if the system files and the data are contained within virtual hard disk (VHD) files. CSV may also provide performance improvements for the live migration process for clustered virtual machines.